SINCE 1828

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leucism

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noun leu·cism \ ˈlü-ˌsi-zəm \

Definition of leucism

:an abnormal condition of reduced pigmentation affecting various animals (such as birds, mammals, and reptiles) that is marked by overall pale color or patches of reduced coloring and is caused by a genetic mutation which inhibits melanin and other pigments from being deposited in feathers, hair, or skin

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leucistic

play \lü-ˈsi-stik\ adjective

Recent Examples of leucism from the Web

Life can be tough for white squirrels, and other animals with leucism.

— joan morris, The Mercury News, "Unusual white squirrel seen cavorting in Walnut Creek," 11 Apr. 2017
There are three ways this can occur: albinism, leucism, and isabellinism.

— National Geographic, "Pictures: Rare White Giraffe and Other Unusually Pale Animals," 28 Jan. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'leucism.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of leucism

borrowed from German Leucismus, from Greek leukós "clear, white" + German -ismus -ism — more at ¹light

NEW! Time Traveler

First Known Use: 1878

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